Webcam not working on HP Pavilion dv7-6b55dx

I've got a question that I hope someone can answer for me. I am unable to get my webcam to work on my laptop. (Model # HP Pavilion dv7-6b55dx). It worked great for a long time but the other day I noticed that I couldn't get it to work at all. I've tried installing and unistalling and then reinstalling the Cyberlink youcam software but it gives me an 'No webcam detected' message when I open the program where in the past, it showed the image of whatever was in front of my webcam. What can I do to make my webcam work again? Do I need drivers or what exactly? I've tried everything I can think of and nothing works. Thanks for any insight anyone can give to me.